From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ben Greear Subject: Re: OOM when adding ipv6 route: How to make available more per-cpu memory? Date: Mon, 08 Nov 2010 10:08:50 -0800 Message-ID: <4CD83CB2.7070809@candelatech.com> References: <4CD43C87.5040403@candelatech.com> <1288980361.2882.1070.camel@edumazet-laptop> <4CD449A5.5070305@candelatech.com> <1288988403.2665.268.camel@edumazet-laptop> <1288995103.2665.653.camel@edumazet-laptop> <4CD49C2F.3060904@candelatech.com> <1289028392.2665.2418.camel@edumazet-laptop> <4CD58B9C.2030006@candelatech.com> <1289214131.2820.187.camel@edumazet-laptop> <4CD83752.1070501@candelatech.com> <1289238912.3167.4.camel@edumazet-laptop> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: NetDev To: Eric Dumazet Return-path: Received: from mail.candelatech.com ([208.74.158.172]:47364 "EHLO ns3.lanforge.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753386Ab0KHSIy (ORCPT ); Mon, 8 Nov 2010 13:08:54 -0500 In-Reply-To: <1289238912.3167.4.camel@edumazet-laptop> Sender: netdev-owner@vger.kernel.org List-ID: On 11/08/2010 09:55 AM, Eric Dumazet wrote: > Le lundi 08 novembre 2010 =C3=A0 09:45 -0800, Ben Greear a =C3=A9crit= : > >> That helps. I'm getting all of the IP addrs set now, but >> having trouble with some of the default gateways (I have one >> routing table per interface). >> >> ./local/sbin/ip -6 route replace default via 2002:9:8::1 dev eth7#45= 8 table 726 >> RTNETLINK answers: No buffer space available >> >> dmesg is full of this: >> >> [247106.294743] ipv6: Neighbour table overflow. >> >> >> A quick look in /proc didn't show a tunable for this, but I'll >> go grub through the code. >> >> As for the route/max_size, it would be nice to see some useful kerne= l >> message in dmesg when this hit. Just telling the user '-ENOMEM' >> is not at all sufficient to help them figure out the problem. > > Sure, patches are welcomed. Apparently nobody yet used ipv6 with so m= any > devices / routes, and this nobody contributed to extend limits. I'll see what I can do. I'm aiming for several thousand IPv6 addrs, so will try to get these limitations ironed out. >> For that matter, why is there such a limit anyway? IPv4 doesn't app= ear >> to have any such limit? > > There are limits for ipv4, much bigger, you probably never noticed. > > > /proc/sys/net/ipv4/route/gc_elasticity:8 > /proc/sys/net/ipv4/route/gc_interval:60 > /proc/sys/net/ipv4/route/gc_min_interval:0 > /proc/sys/net/ipv4/route/gc_min_interval_ms:500 > /proc/sys/net/ipv4/route/gc_thresh:131072 > /proc/sys/net/ipv4/route/gc_timeout:300 > /proc/sys/net/ipv4/route/max_size:2097152<<< HERE > /proc/sys/net/ipv4/route/min_adv_mss:256 > /proc/sys/net/ipv4/route/min_pmtu:552 > /proc/sys/net/ipv4/route/mtu_expires:600 > /proc/sys/net/ipv4/route/redirect_load:2 > /proc/sys/net/ipv4/route/redirect_number:9 > /proc/sys/net/ipv4/route/redirect_silence:2048 > > I suggest followup discussion can got to netdev only, now per-cpu it = not > anymore the problem ? Agreed, and trimmed. Thanks, Ben --=20 Ben Greear Candela Technologies Inc http://www.candelatech.com